The present invention relates to telecommunication techniques. More particularly, the present invention provides an improved MZM linear driver for silicon photonics.
Over the last few decades, the use of communication networks exploded. In the early days Internet, popular applications were limited to emails, bulletin board, and mostly informational and text-based web page surfing, and the amount of data transferred was usually relatively small. Today, Internet and mobile applications demand a huge amount of bandwidth for transferring photo, video, music, and other multimedia files. For example, a social network like Facebook processes more than 500 TB of data daily. With such high demands on data and data transfer, existing data communication systems need to be improved to address these needs.
40-Gbit/s and then 100-Gbit/s data rates over existing single-mode fiber is a target for the next generation of fiber-optic communication networks. The big hangup so far has been the fiber impairments like chromatic dispersion that are slowing the communication signal down. Everything is okay up to 10 Gbits/s plus a little, but beyond that, distortion and attenuation take their toll. Many approaches are proposed on modulation methods for transmitting two or more bits per symbol so that higher communication rates can be achieved. Mach-Zehnder modulators (MZM) can handle the higher data rates but require a driver that is differential with a wide output voltage swing.
But yet many problems as roadblocks for achieving high rate communication are associated with the MZM drivers such as RF loss limit of the traveling wave or amplitude limit of swing voltage. Therefore, improved techniques and methods are desired.